Air passage opening and closing device capable of preventing uncomfortable noise

ABSTRACT

An air passage opening and closing device for controlling an air flow for air-conditioning a vehicle compartment which is adapted to reduce an uncomfortable noise generated when the opening degree of a door such as an air-mixing door is small is provided, wherein a plurality of extending portions ( 7   g ) are provided on tips of the lip seal ( 7   c ). The extending dimension (H) of the extending portion ( 7   g ) is more than or equal to substantially 1 mm and less than or equal to substantially 3 mm, the dimension (B) in the width direction orthogonal to the extending direction in the extending portion ( 7   g ) is more than or equal to substantially 2 mm and less than or equal to substantially 14 mm, and the gap distance (G) between the adjacent extending portions ( 7   g ) is more than or equal to substantially 1 mm and less than or equal to substantially 4 mm.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an air passage opening and closingdevice for opening and closing an air passage and is effective as anair-mixing door for adjusting the ratio of an air flow of a hot air withrespect to that of a cold air (air mixing ratio), a discharging modeswitching door for switching the discharging mode, or the like, in anair conditioner for a vehicle.

2. Description of the Related Art

FIG. 1 is a drawing showing a structure of an indoor unit (the indoorunit is named so because it is arranged inside a vehicle compartment ornear the compartment) of an air conditioner for a vehicle which hasalready been produced as a product and has been distributed on a marketat the time of filing of the present application. FIG. 2 is an enlargedperspective view of A portion in FIG. 1 and FIG. 3 is a sectional viewtaken along the line 3A—3A in FIG. 2.

In FIG. 1, an air-conditioner casing 1 is a duct means which forms anair passage which is furnished in a vehicle compartment and from whichair is discharged to an inside of the compartment. A blower (not shown)for supplying the air into the compartment is provided on a lower frontside of the air-conditioner casing 1 in the drawing.

At the upstream side of an air flow in the air-conditioner casing 1, anevaporator 2 for cooling air discharged into the compartment isaccommodated and all the air discharged from the blower passes throughthe evaporator 2.

At the downstream side of the air flow of the evaporator 2, a heatercore 3 for heating air discharged into the compartment is accommodatedand, at the same time, a bypass passage 4 to allow air, which has passedthrough the evaporator 2, to bypass the heater core 3 and to flow intothe compartment side, is provided.

An air-mixing door 7 is an air flow ratio adjusting means for adjustingthe air flow ratio of a cold air passing through the bypass passage 4with respect to a hot air passing through the heater core 3. Anair-mixing chamber 8 is an air-mixing chamber for mixing the cold airpassing through the bypass passage 4 and the hot air passing through theheater core 3.

At the upper side of the air-mixing chamber 8, a face opening portion 9communicating to a face discharge port (not shown) for discharging airto the upper side of the vehicle compartment through a duct (not shown)and a defroster opening portion 10 communicating to a defrosterdischarge port (not shown) for discharging air to vehicle windows(mainly to a front window glass) through a duct (not shown) areprovided. On the other hand, at the lower side of the air-mixing chamber8, a foot opening portion for discharging air to the lower side of thevehicle compartment.

A face door 11 is an opening and closing means for opening and closingthe face opening portion 9, a defroster door 12 is an opening andclosing means for opening and closing the defroster opening portion 10,and a foot door 13 is an opening and closing means for opening andclosing the foot opening portion.

The air-mixing door 7, the face door 11, the defroster door 12 and thefoot door 13 open and close the respective opening portions thereof byswinging (rotating) rectangular plate-like door bodies thereof, aroundthe rotation axes of the opening portions as a center, by actuators suchas a servo motor, etc. Because of the above configuration, the structureof opening and closing means will be explained below using an air-mixingdoor 7 as an example.

In FIG. 2, an opening portion 1 a is an inlet port continuing to theevaporator 2 in air passages constituted by the air-conditioner casing 1and the air-mixing door 7 is arranged at the upstream side of the airflow in the opening portion 1 a so that it is possible to swing.

The air-mixing door 7 comprises: a substantially rectangular door body 7a for opening and closing the opening portion 1 a; a shaft portion 7 bacting as a swinging shaft of the air-mixing door 7, i.e. the door body7 a; an elastically deformable lip seal 7 c which is arranged on aportion corresponding to the edge portions 1 b of the opening portion 1a and in the edge side of the door body 7 a and closes a gap createdbetween the air-mixing door 7 and the edge portions 1 b of the openingportion 1 a when the opening portion 1 a is closed by the air-mixingdoor 7; an elastically deformable second lip seal 7 d which closes a gapat the shaft portion 7 b side in the edge portions 1 b of the openingportion 1 a; and the like.

Particularly, the door body 7 a and the shaft portion 7 b are made ofhard resin such as polypropylene and the lip seals 7 c, 7 d are made offlexible resin, such as elastomer, or rubber. Both of them areintegrated by integral forming.

The sectional shape of the lip seal 7 c is formed in a V shape, as shownin FIG. 3, so that a portion at which a side 7 e shown at the upper sideof the drawing (FIG. 3) and another side 7 e shown at the lower side ofthe drawing are joined is positioned near to the door body 7 a. The side7 e of the lip seal 7 c at the lower side of the drawing is a seal meansfor closing gaps created between the air-mixing door 7 and the edgeportions 1 b of the opening portion 1 a and the side 7 e of the lip seal7 c at the upper side of the drawing is a seal means for closing gapscreated between the air-mixing door 7 and edge portions 4 a of thebypass passage 4 (refer to FIG. 1).

At the tips of the lip seal 7 c, i.e. the tip sides of the sides 7 e,protruding portions 7 f protruding toward the edge portions 1 b andtoward the edge portions 4 a are integrally formed with the lip seal 7 cand, thereby, the sealing ability of the lip seal 7 c is improved bycontacting the tips of the protruding portions 7 f to the edge portions1 b and 4 a.

Concretely, the protruding portion 7 f totally forms a substantiallyC-shaped protruding line continuously provided on the totallysubstantially C-shaped lip seal 7 c in a similar state to the lip seal 7c which is formed in a substantially C-shape on the end of the door body7 a.

The second lip seal 7 d is formed so that two sides 7 e of the lip seal7 c forming a V shape are combined into one side and the other structurethereof is the same as that of the lip seal 7 c.

When the opening degree of the air-mixing door 7 is small, anuncomfortable noise such as “hyu”, “pyu” or “pyy” is likely to occur.The cause of the noise is generally as described below.

That is, when the opening degree of the air-mixing door 7 is small, asshown in FIG. 4, there may be a case in which air flows through arelatively small gap (a short distance) formed between the edge portion1 b of the opening portion 1 a and the air-mixing door 7 in a laminarflow without being transformed into a turbulent flow. Part of an airflow after flowing through the air-mixing door 7 creates an exfoliatinglayer (an exfoliating flow) exfoliating from a main air flow, at theback side of the air-mixing door 7, and in a case in which theexfoliating layer grows into a row of vortexes, an uncomfortable noisesuch as “hyu” is created.

A means for reducing a noise caused by a row of vortexes created whenair flows through a relatively small gap formed between an edge portionof an opening portion and an opening and closing door was conventionallyrealized by forming recesses and protrusions on the tip side of a lipseal to disturb an air flow passing through a gap between the lip sealand the edge portion of the opening portion and to prevent the air flowfrom being formed into a laminar flow, with a result preventing a row ofvortexes from being created (for example, refer to Patent Document 1).

[Patent Document 1] Japanese Utility Model Publication No. 2,570,855

As the invention disclosed in Patent Document 1, however, relates to anopening and closing door for opening and closing a discharge port suchas a face discharging port directly facing an inside of a vehiclecompartment, it can not be applied to the air-mixing door 7 arranged inthe air-conditioner casing 1, and the like, without modification and cannot prevent efficiently the occurrence of a row of vortexes.

SUMMARY OF THE INVENTION

The present invention has been developed with the above-mentionedproblems being taken into consideration, the first object thereof is toprovide a novel air passage opening and closing device different fromthe prior art and the second object thereof is to reduce uncomfortablenoise by preventing the occurrence of vortexes.

To realize the above-mentioned objects, in a first aspect of the presentinvention, an air passage opening and closing device for controlling anair flow for air-conditioning a vehicle compartment is disclosed whichcomprises: a casing (1) of an air conditioner for a vehicle, which hasan opening portion (1 a) through which air flows, forms air passages (4,8) and is provided with at least an evaporator (2); and an opening andclosing door (7) which opens and closes the opening portion (1 a) andmixes an air from the evaporator (2) with a hot air or switches airdischarging modes at least between a face mode and a foot mode; whereinon a portion of an end side of the opening and closing door (7),corresponding to an edge portion of the opening portion (1 a), anelastically deformable lip seal (7 c) for closing a gap formed betweenthe opening and closing door (7) and the edge portion of the openingportion (1 a) when the opening portion (1 a) is closed by the openingand closing door (7) is provided, and on a tip of the lip seal (7 c) aplurality of extending portions (7 g) are provided; and wherein theextending dimension (H) of the extending portions (7 g) is more than orequal to substantially 1 mm and less than or equal to substantially 3mm, the dimension (B) in the width direction orthogonal to the extendingdirection in the extending portions (7 g) is more than or equal tosubstantially 2 mm and less than or equal to substantially 14 mm, andthe gap distance (G) between the adjacent extending portions (7 g) ismore than or equal to substantially 1 mm and less than or equal tosubstantially 4 mm.

By this configuration, it is possible to disturb and mix an air flowpassing through the gap between the lip seal (7 c) and the edge potionof the opening portion (1 a) and, therefore, it is possible to restrictthe generation of a row of vortexes by preventing the air flow frombecoming a laminar flow. As a result, it is possible to prevent theoccurrence of uncomfortable abnormal noise such as “hyu”.

In addition, as the extending dimension (H) of the extending portions (7g) is more than or equal to substantially 1 mm and less than or equal tosubstantially 3 mm, the dimension (B) in the width direction orthogonalto the extending direction in the extending portions (7 g) is more thanor equal to substantially 2 mm and less than or equal to substantially14 mm, and the gap distance (G) between the adjacent extending portions(7 g) is more than or equal to substantially 1 mm and less than or equalto substantially 4 mm, it is clear from FIG. 10, described later, thatit is possible to reduce the occurrence of the abnormal noise byensuring to prevent the generation of the row of vortexes.

In a second aspect of the present invention, an air passage opening andclosing device is disclosed which comprises: a casing (1) for airconditioning of a vehicle, which has an opening portion (1 a) throughwhich air flows, forms air passages (4, 8); and an opening and closingdoor (7) which opens and closes the opening portion (1 a); and ischaracterized in that; on a portion of an end side of the opening andclosing door (7), corresponding to an edge portion of the openingportion (1 a), an elastically deformable lip seal (7 c) for closing agap formed between the opening and closing door (7) and the edge portionof the opening portion (1 a) when the opening portion (1 a) is closed bythe opening and closing door (7) is provided, and on tips of the lipseal (7 c) a plurality of extending portions (7 g) are provided; and inthat the extending dimension (H) of the extending portions (7 g) is morethan or equal to substantially 1.5 mm and less than or equal tosubstantially 3 mm, the dimension (B) in the width direction orthogonalto the extending direction in the extending portions (7 g) is more thanor equal to substantially 5 mm and less than or equal to substantially10 mm, and the gap distance (G) between the adjacent extending portions(7 g) is more than or equal to substantially 2 mm and less than or equalto substantially 4 mm.

By this configuration, it is possible to disturb and mix an air flowpassing through the gap between the lip seal (7 c) and the edge potionof the opening portion (1 a) and, therefore, it is possible to restrictthe generation of a row of vortexes by preventing the air flow frombecoming a laminar flow. As a result, it is possible to prevent theoccurrence of uncomfortable abnormal noise such as “hyu”.

Moreover, as the extending dimension (H) of the extending portions (7 g)is more than or equal to substantially 1.5 mm and less than or equal tosubstantially 3 mm, the dimension (B) in the width direction orthogonalto the extending direction in the extending portions (7 g) is more thanor equal to substantially 5 mm and less than or equal to substantially10 mm, and the gap distance (G) between the adjacent extending portions(7 g) is more than or equal to substantially 2 mm and less than or equalto substantially 4 mm, it is clear from FIG. 10, described later, thatit is possible to reduce the occurrence of the abnormal noise byensuring to prevent the generation of the row of vortexes.

In a third aspect of the present invention, an air passage opening andclosing device is characterized in that; on a root side of the extendingportion (7 g), protruding portions (7 f) in a linear shape whichprotrude toward the edge portion of the opening portion (1 a) and comeinto contact with the edge portions when the opening and closing door(7) is closed are integrally formed.

In a fourth aspect of the present invention, an air passage opening andclosing device is characterized in that the sectional shape of the lipseal (7 c) is a V shape in which a portion thereof near the opening andclosing door (7) protrudes.

In a fifth aspect of the present invention, an air passage opening andclosing device is characterized in that the lip seal (7 c) and theextending portions (7 g) provided on the tip of the lip seal (7 c) areintegrally formed to each other.

In a sixth aspect of the present invention, an air passage opening andclosing device is characterized in that the lip seal (7 c) and theopening and closing door (7) are integrally formed to each other.

In a seventh aspect of the present invention, an air passage opening andclosing device is characterized in that the V shape of the lip seal (7c) which extends toward the opening and closing door (7) has two sides(2 e) which separate further in a direction from the tip of the openingand closing door (7) to tips of the sides (2 e).

In an eighth aspect of the present invention, an air passage opening andclosing device is disclosed wherein the opening and closing doorcomprises any one of: an air-mixing door (7) for mixing air in thecasing (1) of the air conditioner for a vehicle; a face door (11) fordirecting an air flow from the casing (1) of the air conditioner for avehicle toward a passenger's face; a defroster door (12) for directingan air flow from the casing (1) of the air conditioner for a vehicletoward a windshield direction; and a foot door (13) for directing an airflow from the casing (1) of the air conditioner for a vehicle toward apassenger's feet; and wherein all of these doors are rectangular, thelength of shorter sides thereof is in a range between substantially 3 cmand substantially 10 cm, and the length of longer sides thereof is in arange between substantially 5 cm and substantially 30 cm.

In an ninth aspect of the present invention, an air passage opening andclosing device for controlling an air flow for air-conditioning avehicle compartment comprises: a casing (1) of an air conditioner for avehicle which has an opening portion (1 a) through which air flows andforms air passages (4, 8); and an opening and closing door (7) whichopens and closes the opening portion (1 a); wherein on a portion of anend side of the opening and closing door (7), corresponding to an edgeportion of the opening portion (1 a), an elastically deformable lip seal(7 c) for closing a gap formed between the opening and closing door (7)and the edge portion of the opening portion (1 a) when the openingportion (1 a) is closed by the opening and closing door (7) is provided;wherein the lip seal (7 c) is joined to a tip of the opening and closingdoor (7), the lip seal (7 c) is configured to seal the opening portion(1 a) so that an end of the lip seal (7 c) comes into contact with theedge portion (1 b) of the opening portion (1 a) so as to block an airflow when the opening and closing door (7) closes the opening portion (1a) through which air flows, and the lip seal (7 c) comprises sides (7e), a base portion (7K) of the sides, protruding portions (7 f), and anumber of extending portions (7 g); wherein the protruding portion (7 f)is provided on a tip of the side (7 e) so as to protrude toward the edgeportion (1 b) of the opening portion (1 a) in a state in which theprotruding portion (7 f) linearly extends along the tip ends of theopening and closing door (7) and the protruding portion (7 f) comes intocontact with the edge portion (1 b) of the opening portion (1 a) whenthe opening and closing door (7) is closed; and wherein a number of theextending portions (7 g) are integrally formed with the respective sides(7 e) in a row along the protruding portions (7 f).

In a tenth aspect of the present invention, an air passage opening andclosing device is characterized in that the tips of the extendingportions (7 g) form a tip of the lip seal (7 c), the extending directionof the extending portions (7 g) is set to further from the edge portion(1 b) of the opening portion (1 a) than an extending direction of theside (7 e), and the extending direction of the outside of the extendingportion (7 g) and the extending direction of the outside of the side (7e) intersect with each other by a predetermined angle (θ).

In an eleventh aspect of the present invention, an air passage openingand closing device is characterized in that the sides (7 e) are formedas a pair, a pair of the sides (7 e) are joined at the base portion (7k), as a pair of the sides (7 e) are formed so that the inside distancebetween a pair of the sides (7 e) increases in a direction from the tipof the opening and closing door (7) to the tip of the lip seal (7 c),the lip seal (7 c) is totally formed in a V shape, and the protrudingportion (7 f) is provided on each tip of a pair of the sides (7 e) so asto protrude toward the outside of the side opposite to the insidethereof.

In a twelfth aspect of the present invention, an air passage opening andclosing device is characterized in that tips of the extending portions(7 g) form a tip of the lip seal (7 c), the extending direction of theextending portion (7 g) is set more inside than the extending directionof the each side (7 e), and the extending direction of the outside ofthe extending portion (7 g) and the extending direction of the outsideof the each side (7 e) intersect with each other by a predeterminedangle (θ).

The symbols in the parentheses attached to each means described aboveindicate correspondence with specific means in embodiments which will bedescribed later.

The present invention may be more fully understood from the descriptionof the preferred embodiments of the invention set forth below, togetherwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a perspective view showing a structure of an indoor unit of anair conditioner for a vehicle.

FIG. 2 is an enlarged perspective view of the A portion in FIG. 1.

FIG. 3 is a sectional view taken along the line 3A—3A in FIG. 2.

FIG. 4 is a drawing for explaining the cause of abnormal noise.

FIG. 5 is a perspective view showing an area around an air-mixing door 7and an opening portion in an embodiment according to the presentinvention.

FIG. 6 is a sectional view taken along the line 6A—6A in FIG. 5.

FIG. 7 is an enlarged perspective view of a lip seal in an embodimentaccording to the present invention.

FIG. 8 is a drawing viewed in the A arrow direction in FIG. 6.

FIG. 9 is a drawing viewed in the B arrow direction in FIG. 6.

FIG. 10 is a graph for showing whether abnormal noise occurs or not.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

In a first embodiment, an air passage opening and closing deviceaccording to the present invention is applied to an indoor unit of anair conditioner for a vehicle.

The components of the indoor unit according to the present embodiment,other than an air-mixing door 7, a face door 11, a defroster door 12 anda foot door 13, are the same as the components included in the exemplaryindoor unit of the prior art which has been described in “Description ofthe Related Art” in this specification. The difference of the indoorunit according to the present embodiment with respect to that of theexample of the prior art is in the shapes of lip seals of the air-mixingdoor 7, the face door 11, the defroster door 12 and the foot door 13.

The air-mixing door 7 mixes air in a casing 1 of an air conditioner fora vehicle, the face door 11 directs an air flow towards a face of apassenger from the casing, the defroster door 12 directs an air flowtowards a windshield from the casing, the foot door 13 directs an airflow towards the feet of a passenger from the casing. All of these doorshave a rectangular shape and the length of the short sides thereof is ina range between 3 cm and 10 cm and the length of the long sides thereofis in a range between 5 cm and 30 cm.

The air-mixing door 7, the face door 11, the defroster door 12 and thefoot door 13 open and close their opening portions by swinging(rotating) the rectangular plate-like door bodies thereof, around therotation axes thereof as a center, by actuators such as a servo motor,etc., as described above, and the basic constructions in the air-mixingdoor 7, the face door 11, the defroster door 12 and the foot door 13 arecommon and, therefore, the difference of the air-mixing door 7 withrespect to that of the example of the prior art is mainly describedbelow, as an example, in order to explain the present embodiment.

FIG. 5 is a perspective view showing an area near the air-mixing door 7and an opening portion 1 a in the present embodiment, FIG. 6 is asectional view taken along the line 6A—6A in FIG. 5, FIG. 7 is anenlarged perspective view of a lip seal 7 c, FIG. 8 is a drawing viewedfrom A arrow direction in FIG. 6 and FIG. 9 is a drawing viewed from Barrow direction in FIG. 6.

In the present embodiment, a plurality of extending portions 7 g whichextend in the direction parallel to a door body 7 a are integrallyformed with the lip seal 7 c, as shown in FIG. 7, at the tip side of thelip seal 7 c, that is, the tip side of a side 7 e, in comparison withthe lip seal 7 c of the air-mixing door 7 according to the example ofthe prior art shown in FIG. 3 and the like.

To be specific, the lip seal 7 c is coupled to the tip of the door body7 a, the lip seal 7 c acts as a seal for blocking an air flow by a wayin which the lip seal 7 c comes into contact with the edge portion 1 bof the opening portion 1 a when the door body closes the opening portionthrough which air flows.

The lip seal 7 c comprises a pair of sides 7 e, a base portion 7 kformed by joining the sides, a pair of protruding portions 7 f and anumber of extending portions 7 g.

The distance of the space between two sides 7 e of the lip seal 7 c,that is an inside, is increased as it proceeds in a direction from thetip of the door body 7 a to the tip of the lip seals 7 c. In otherwords, the lip seal 7 c is totally formed in a V shape with a pair ofsides 7 e of the lip seal 7 c.

The protruding portions 7 f which protrude to the outside opposite tothe inside, described above, are provided on the tip of a pair of sides7 e respectively, the protruding portions 7 f are formed in a linearline which extends along the tip of the door body 7 a and, therefore,improves the sealing effect thereof as the protruding portion 7 f comesinto contact with the edge portion 1 b of the opening portion 1 a.

In addition, a number of the extending portions 7 g for preventing awhistle-like noise are formed in a row together with each side 7 e alongthe protruding portions 7 f, wherein the extending direction of theextending portions 7 g is approximate to the extending direction of eachside 7 e.

The tips of the extending portions 7 g forms the tip of the lip seal 7 cand the extending direction of the extending portions 7 g is locatedmore inside than the extending direction of the respective sides 7 e sothat the outside extending direction of the extending portions 7 gintersects with the outside extending direction of the respective sides7 e by a predetermined angle (θ). Due to the intersection, theprotruding portion 7 f easily comes into contact with the edge portion 1b of the opening portion 1 a and, therefore, the protruding portion 7 fsecurely provides a sealing portion. Because of this configuration, evenif a seal is in an incomplete state the extending portions 7 g preventabnormal noise like noise caused by a blowing wind, etc.

In this case, the extending dimension H (refer to FIG. 9) of theextending portions 7 g is more than or equal to about 1 mm and less thanor equal to about 3 mm, the dimension B (refer to FIG. 9) in the widthdirection orthogonal to the extending direction in the extendingportions 7 g is more than or equal to about 2 mm and less than or equalto about 14 mm, and the distance G (refer to FIG. 9) between theadjacent extending portions 7 g is more than or equal to about 1 mm andless than or equal to about 4 mm.

In the present embodiment, the extending dimension H of the extendingportions 7 g is set to about 2 mm, the dimension B in the widthdirection orthogonal to the extending direction in the extendingportions 7 g is set to 9 mm, and the distance G between the adjacentextending portions 7 g is set to 3 mm.

Moreover, in the present embodiment, the angle between two sides 7 e isabout 60 degree, the door body 7 a and the shaft portion 7 b are made ofa hard resin such as polypropylene etc., the lip seals 7 c, 7 d are madeof a flexible resin such as elastomer etc. and they are integrallymolded in order to be integrated.

The protruding portion 7 f is formed in a semicircular sectional shapewith a radius more than or equal to about 0.5 mm and less than or equalto about 0.6 mm.

The functions and effects of the present embodiment will be describedbelow.

In the present embodiment, as a plurality of the extending portions 7 gare provided on the tip side of the lip seal 7 c, the air flow passingthrough a gap between the lip seal 7 c and the edge portion 1 b of theopening portion 1 a can be disturbed and mixed.

Accordingly, it is possible to prevent the air flow from becoming alaminar flow so as to restrict the occurrence of a row of vortexes. As aresult, it is possible to prevent the occurrence of uncomfortableabnormal noise such as “hyu”.

In addition, as the extending dimension H of the extending portions 7 gis more than or equal to about 1 mm and less than or equal to about 3mm, the dimension B in the width direction orthogonal to the extendingdirection in the extending portions 7 g is more than or equal to about 2mm and less than or equal to about 14 mm and the distance G between theadjacent extending portions 7 g is more than or equal to about 1 mm andless than or equal to about 4 mm, it is obvious from the graph of thetest results shown in FIG. 10 that it is possible to prevent surely theoccurrence of a row of vortexes in order to reduce abnormal noise.

The graph of the test results shown in FIG. 10 indicates test results ina condition in which the air flow rate is set between 10 to 40 m3/h andthe gap between the lip seal 7 c and the edge portion 1 b is set between0 to 10 mm and the reduction of the noise is confirmed by the auditorysense.

Second Embodiment

In a second embodiment, the extending dimension H of the extendingportions 7 g is more than or equal to about 1.5 mm and less than orequal to about 3 mm, the dimension B in the width direction orthogonalto the extending direction in the extending portions 7 g is more than orequal to about 5 mm and less than or equal to about 10 mm and thedistance G between the adjacent extending portions 7 g is more than orequal to about 2 mm and less than or equal to about 4 mm.

In this configuration, as the air flow passing through a gap between thelip seal 7 c and the edge portion 1 b of the opening portion 1 a can bedisturbed and mixed, it is possible to prevent the air flow frombecoming a laminar flow so as to restrict the occurrence of a row ofvortexes. As a result, it is possible to prevent the occurrence ofuncomfortable abnormal noise such as “hyu”.

Other Embodiment

The embodiments described above are the same as the example of prior artexplained in “Description of the Related Art” other than the shape ofthe lip seal 7 c, but the present invention is not limited to theseembodiments.

In the embodiments described above, the shape of the extending portions7 g is made to be rectangular, but the present invention is not limitedto these embodiments and it may be, for example, triangular orsemicircular.

The present invention meets the basic concept of the invention disclosedin the claims, but the present invention is not limited to theembodiments described above.

For example, the lip seal need not be made in a V shape and it may beone having one side extending from the tip of the door.

The lip seal need not be provided with extending portions on each side,respectively, even if the shape thereof is a V shape and the means forpreventing abnormal noise like noise caused by whistling, etc. may beprovided on only the required side of them.

In addition, the shapes of extending portions arranged together need notbe the same and the lip seal may be configured by combining extendingportions with various shapes with dimensions within a specific range.

While the invention has been described by reference to specificembodiments chosen for the purposes of illustration, it should beapparent that numerous modifications could be made, thereto by thoseskilled in the art, without departing from the basic concept and scopeof the invention.

1. An air passage opening and closing device for controlling an air flowfor air-conditioning a vehicle compartment comprising: a casing of anair conditioner for a vehicle which has an opening portion through whichair flows, forms air passages and is provided with at least anevaporator; and an opening and closing door which opens and closes theopening portion and mixes air from the evaporator with hot air orswitches an air discharging mode at least between a face mode and a footmode; wherein on a portion of an end side of the opening and closingdoor, corresponding to an edge portion of the opening portion, anelastically deformable lip seal for closing a gap formed between theopening and closing door and the edge portion of the opening portionwhen the opening portion is closed by the opening and closing door isprovided, and on a tip of the lip seal a plurality of extending portionsare provided; and wherein an extending dimension of the extendingportions is more than or equal to substantially 1 mm and less than orequal to substantially 3 mm, a dimension in a width direction orthogonalto the extending direction in the extending portions is more than orequal to 2 mm and less than or equal to 14 mm, and a gap distancebetween adjacent extending portions is more than or equal to 1 mm andless than or equal to 4 mm.
 2. An air passage opening and closing deviceas set forth in claim 1, wherein the extending dimension of theextending portions provided on the tip of the lip seal is more than orequal to 1.5 mm and less than or equal to 3 mm, the dimension in thewidth direction orthogonal to the extending direction in the extendingportion is more than or equal to 5 mm and less than or equal to 10 mm,and the gap distance between the adjacent extending portions is morethan or equal to 2 mm and less than or equal to 4 mm.
 3. An air passageopening and closing device as set forth in claim 1, wherein, on a rootside of the extending portion, protruding portions in a linear shapewhich protrude toward the edge portion of the opening portion and comeinto contact with the edge portions when the opening and closing door isclosed are integrally formed.
 4. An air passage opening and closingdevice as set forth in claim 1, wherein a sectional shape of the lipseal is a V shape in which a portion thereof near the opening andclosing door protrudes.
 5. An air passage opening and closing device asset forth in claim 4, wherein the V shape of the lip seal which extendstoward the opening and closing door has two sides which separate furtherin a direction from the tip of the opening and closing door toward tipsof the sides.
 6. An air passage opening and closing device as set forthin claim 1, wherein the lip seal and the extending portions provided onthe tip of the lip seal are integrally formed.
 7. An air passage openingand closing device as set forth in claim 1, wherein the lip seal and theopening and closing door are integrally formed.
 8. An air passageopening and closing device as set forth in claim 1, wherein the openingand closing door comprises any one of: an air-mixing door for mixing airin the casing of the air conditioner for a vehicle; a face door fordirecting air flow from the casing of the air conditioner for a vehicletoward a passenger's face; a defroster door for directing air flow fromthe casing of the air conditioner for a vehicle toward a windshielddirection; and a foot door for directing air flow from the casing of theair conditioner for a vehicle toward a passenger's feet; and wherein allof these doors are rectangular, a length of shorter sides thereof is ina range between 3 cm and 10 cm, and a length of longer sides thereof isin a range between 5 cm and 30 cm.
 9. An air passage opening and closingdevice for controlling an air flow for air-conditioning a vehiclecompartment comprising: a casing of an air conditioner for a vehiclewhich has an opening portion through which air flows and forms airpassages; and an opening and closing door which opens and closes theopening portion; wherein on a portion of an end side of the opening andclosing door, corresponding to an edge portion of the opening portion,an elastically deformable lip seal for closing a gap formed between theopening and closing door and the edge portion of the opening portionwhen the opening portion is closed by the opening and closing door, isprovided; wherein the lip seal is joined to a tip of the opening andclosing door, the lip seal is configured to seal the opening portion sothat an end of the lip seal comes into contact with the edge portion ofthe opening portion so as to block air flow when the opening and closingdoor closes the opening portion through which air flows, and the lipseal comprises; a base portion joined to the tip of the opening andclosing door, a pair of sides extending outward from the base portion, aprotruding portion extending outwardly from a surface on each side ofthe pair of sides and a plurality of extending portions extendingoutward from each protruding portion, each of the protruding portionsextending along the entire tip of the opening and closing door and oneof the protruding portions comes into contact with the edge portion ofthe opening portion when the opening and closing door is closed; andwherein the extending portions are integrally formed with a respectiveside in a row extending outward from the protruding portions.
 10. An airpassage opening and closing device as set forth in claim 9, wherein tipsof the extending portions form a tip of the lip seal, an extendingdirection of the extending portions is set further from the edge portionof the opening portion than an extending direction of the side, and anextending direction of an outside of the extending portion and anextending direction of an outside of the side intersect with each otherby a predetermined angle.
 11. An air passage opening and closing deviceas set forth in claim 9, wherein; the pair of the sides are joined atthe base portion; the pair of the sides are formed so that an insidedistance between the pair of the sides increases in a direction from thetip of the opening and closing door to the tip of the lip seal, the lipseal is totally formed in a V shape; and the protruding portion isprovided on each tip of the pair of the sides so as to protrude towardthe outside of the side opposite to the inside thereof.
 12. An airpassage opening and closing device as set forth in claim 11, whereintips of the extending portions form a tip of the lip seal, an extendingdirection of the extending portion is set more inside than an extendingdirection of the each side, and an extending direction of an outside ofthe extending portion and an extending direction of an outside of theeach side intersect at a predetermined angle.